JSFiddle - React, Tailwind, and code Playground

HTML

<div class="thumbnails">
  <img src="http://icons.iconarchive.com/icons/iconshow/button-design-pack/128/01-Globe-icon.png" data-big="01-Globe-icon.png" class="thumb" />
  <img src="http://icons.iconarchive.com/icons/iconshow/button-design-pack/128/02-Basket-icon.png" data-big="02-Basket-icon.png" class="thumb" />
</div>
<div class="bigbox">
  <img src="http://icons.iconarchive.com/icons/iconshow/button-design-pack/128/01-Globe-icon.png" class="big" />
</div>

JavaScript

$(".thumb").hover( function() {
  var big = "http://icons.iconarchive.com/icons/iconshow/button-design-pack/128/" + $(this).attr("data-big");
  $(".big").attr("src", big);
});